This grant is for the operation of a General Clinical Research Center, at a leel of 1200 "A" days annually. The principal areas of study are: 1. Metabolic and hormonal abnormalities in acute and chronic renal insufficiency. 2. Gastrointestinal hormone physiology. 3. Metabolic and hormonal abnormalities in boesity and hyperlipidemia. 4. Hormonal, bacteriological, and bile acid abnormalities in breast cancer and colon cancer. 5. Pediatric studies in lead poisoning, drug effects on metabolic systems, the calcium-phosphorus-vitamin D-parathormone system, and the polycystic ovary syndrome. 6. Thyroid hormone regulation. 7. Hormonal studies in psychiatric disease. 8. Chronobiology and neuroendocrine regulation.